Drawing frame assembly



April 22, 1952 2,593,478

R. B. NEWTON DRAWING FRAME ASSEMBLY Filed Sept. 28, 1944 2 SHEET SSHEET1 IN V EN TOR.

JQZZB/Wega A ril 22, 1952 H R. B. NEWTON 2,593,473

DRAWING FRAME ASSEMBLY I Filed Sept 28,. 1944 2 SHEETS-SHEETQ 2 1 43 45Y Ja \51 49 INVENT R.

Patented Apr. 22, 1952 UNITED STATES PATENT OFFICE;

2,593,478 DRAWING FRAME ASSEMBLY Russell 3., Newton llanville, Va.,assignor, b'y mesne assignments,-,to Dan River Mills, 111001! p6rated,'acorporation of Virginia 7 Application September 23, 1944, Serial No.556,154-

This invention relates to the drafting of. cotton, and particularly tothe drafting of cotton in which a clear of a revolving type is used in.connection with upper draf'tin'grolls which cooperate with a clearer ina novel manner;

In the manufacture of cotton yarns, the draw-. ing process followscarding and combing operations and consists in taking the roving orsliver, and by drawing it through a series of three or more rolls, thecotton is made more compact'arid. drawn out and the fibers paralleled.Thisset of drawing rolls forms a part ofwhat is known as a drawing frameassembly and is usually so a; ranged that the first set of rolls movesslowly and each succeeding set moves at a higher speed so the roving isextended by the cotton fibers sliding past one another.

In the drawing of the cotton fibers two main problems have confrontedtextile machinery de-' signers, the first being the provision of drawingrolls of such shape and surface characteristics that the sliver orroving would be attenuated a considerable amount but without pulling itapart; the second problem being the removal of the loose and shortfibers from the roving, it being desirable to permanently remove all theloose and short:

fibers and at the same time keep the drawingrol-l-s clean and furthermake it possible to easily remove the collected short fibers.

Many attempts have beenmade to design drafting frame assemblies in orderto solve'the above metal roll which meshed with'the lower roll, butsuchmeshed rolls have been found tobe objectionable due to the fact thatmetal against metal hasatendency to break the cottonr fibers passingtherethrough.

Leather has also been. used'considerably'for the upper pressure rollsbut has a-disadvantageqtl'iat' it has to go through a" special. tanning.process inv order to give the proper frictional surface'foreflL' cientoperation, and its surface is alsoveryeasily injured and unless properlymounted flattens easily while in use. considerable extent both as alayer of cork" and as acompound; cork having about the samefrio-f 5tionalproper-ties as specially prepared leatl-i'e'r and Cork hasalsobeen used to a" Glaima (01. 19

. 2 also similar defects. In addition to the above objections to leatherand cork, one of the biggest defects i'n' the use of such materialintextile drawing rolls has been the cooperation between such leather orcork drawing rolls and the belt of the clearer which issupposed toeollectthe excess material picked up by the drawing rolls because, whilethe surface ofthe drawing rolls-may be such as to obtain properattenuatior'r-of the roving o1 sliver; this same surface has-heretoforealways presented dimculties in its cooperation with the clearer. I

problem of getting rid of the short fibers and stretching the rovingand. the like and keep- 1 ing' the drawing rolls clean, was firstattacked by using a flat top stationary clearer which worked fairlysatisfactorily if itwere lifted up at very frequent intervals andcleaned, but with thousands of such clearers to take care of in theaverage cotton mill it obviously is quite a job to lift'upstationary'dealers with necessary regularity. After the stationary clearer had beenused fora good many years, attempts were made in Europe and the UnitedStates to utilize a'revolving clearer'of the general type disclosed inthe British patent to Peip'er No. 4,491 of 1876. However, the drawingframe assembly of the type shown in Peiper was not generallysuccessful'because the revolving clearer surface would not ffelt upuniformlyybut would, vbecause of the] nature'of the surfaces of thedrawing rolls, cause the formation of small rolls or rat tails whichsmall" rolls of clearer waste would persistently go over' thedrawi'n'frollers and back down'into the roving orsliver, thus making irregularand irn'' perfect yarn and frequently breaking the end.

Subsequent to the revolving clearer-s and drawing frame assemblies ofthe Peiper type, attempts were made the textile industry to use arevolving positive drive clearer of the type shown inthe British patentto Ermen No. 3,386 of 1873'. Such positive drive clearers of the Ermentypiusually' utilized'som type of a rake for picking upthe clearer wasteofi of the clearer belt. These positive" drive rake type revolvingclearers worked fairly satisfactorily but after a relatively shortperi'od ofi operation thesurface of the belt would e we smooth with theresult that rat tails" would beformed and be carried back into theroving or sliver. Such positive drive'rake type clearers such as lilrmenwere generally discarded by the industry-and up totheintroduction of thepresent invention the most general practice ili'the Urii t'edst'ats wasto use a combination of :a stafcanary-clearer with each drawing rolLthesur faces of the drawing rolls being usually of leather, cork or metal.

Recent attempts in the drafting of cotton contemplated the use ofsynthetic drawing rolls with a stationary clearer, but such attemptswere not successful because this combination of synthetic roll andstationary clearer resulted in the forming of what are known as eyebrowswhich were the result of the excessive accumulation of short fibers inthe angle between the drawing roll and the surface of the stationaryclearer; such accumulation of short fibers building up into the shape ofan eyebrow and then dropping down onto the roving or sliver.

I have discovered that the surface of the drafting roll can be made of asynthetic rubber like material of such peculiar properties that thecoefficient of friction of such surface is not only ideal for theattenuation of the fibers in the drawing of the roving or sliver butsuch coefficient of friction so cooperates with the surface of arevolving clearer that the loose and short fibers are picked up from andcarried out of the roving without the forming of any frat tails oreyebrows. The drawing rolls are kept clean and the waste is felteduniformly on the revolving clearer cloth. 7

An important feature of this invention is the fact that by using asynthetic drawing roll of definite surface characteristics there issufiicient friction whereby it may be used with. excellent results witha revolving type clearer because the friction of the rolls pushes thecotton waste against the clearer cloth to the extent that it forms avery firm felted condition;' this same friction surface makes itpossible to make use of a medium sized roll placed above the pressureroll to drive the clearer cloth without any additional mechanicaldevice. This combination of synthetic pressure roll and revolvingclearer results in the production of much'better cotton yarn with muchless supervision labor and maintenance cost than haspreviously beenpossible.

Other objects of the present invention include the structure of thedrawing frame assembly as will be brought outin the specification andclaims. a

In-the drawings: I

Figure 1 is a vertical sectional view taken through a drawing frameassembly embodying the principles of the present invention, a clearerbeing shown in position contacting the top rolls of a textile machineemploying drawing or at-' tenuating rolls; and in addition showing as apossible modification a clearer contacting the bottom rolls.

Figure 2 is a perspective view of the clearer shown in Figure 1;

Figure 3 is a vertical section taken on the line 3 3 of Figure 4.

Figure 4 is a section taken on the'line 4-4 of Figure 1.

Figure 5 is a perspective of a clearer embodying a plurality of cleareraprons, and

Figure 6 is a bottom plan view of the clearer shown in Figure 5.

Referring to the drawings, Figure 1 shows conventionally a drawing frameassembly of a. textile machine I having a series of pairsofdrawing orattenuating rolls 2.

In my preferred arrangement the bottom IQ of each pair of rolls 2 is adriven roll and formed of metal and each one of the top rollshas a layer2a of synthetic rubber. The composition 2a of the surface of these upperpressure rolls may be any one of the four compositions set forth in thepatent to Rockoif No. 2,341,656 of February 15, 1944, or may be thebutadieneacrylic nitrile 'co-polymer composition set forth in the patentto Rockolf No. 2,304,656 of December 8, 1942. Of the compositions setforth in the Rockofi Patent No. 2,341,656, the preferred one iscomposition #2 which is known as the perbunan composition Parts byweight 'Perbunan (butadiene polymerization product) Zinc oxide 5 Sulfur2 Altax (benzothiazyl disulfide) l Whiting 30 Mineral oil 10 Cottonfiber 30 Vulcanizing: 30 minutes at 300 F. steam cure.

Rolls formed of synthetic material such as shown in the Rockofi patentshave been made and used for draft aprons and the like in the textileindustry, but I believe I am the first to appreciate the peculiarcoeificient of friction characteristics of ,this synthetic material foruse as pressure rolls in a drafting apron assembly and in combinationwith a revolving clearer.

The rolls 2 are arranged in vertical pairs, with the upper rolls of thevarious pairs in horizontal alignment and the lower rolls in horizontalalignment. The pairs of rolls are driven at progressively increasingspeeds, the back pair 3 rotating at the slowest speed and the front pair4 the fastest. Conventional drive mechanism, not shown, rotates therolls. This provides stretching and slimming of the material 5 betweeneach pair of rolls.

The clearer which is indicated at 6 has a housing? of sheet materialwhich covers the top, the metal being downturned to form flanges 8 and 9at the front and rear. The housing is braced by frame members If! and IIextending from front to back which have downwardly projecting hinge lugsl2 and [3 at the rear to pivotally connect the clearer to the textilemachine frame. Bearing blocks l4 and I5 are positioned against theunderside of the housing with the cut-away portions receiving bosses l8and i9 which project from the housing. Strips 2E! and 2|, extending thefull length of the bearing blocks, have screws 22 and 23 passing throughthem; the screws threading into the bosses l8 and I9 and securing theblocks within the housing.

The bearing blocks are grooved as at 24, 25, 26

' and 21, 28, 29 to slidably receive the reduced ends of clearer rollers30, 3| and 32. The grooves are so spaced that the clearer rollers, whenin position, will occupy positions directly overlying certain rolls ofthe drawing mechanism 2. One of the clearer rollers will be over thefront pair of rolls 2, another will be over the back pair, and one ormore clearer rollers will be positioned above one or more of theremaining pairs. All of the clearer rollers, with the exception ofroller 32 which is over the back drawing rolls, are of relatively lightWeight, while the roller 32 is weighted and quite heavy. An apron 33 ofwool or other endless fabric material passes around the clearer rollersand is in contact with the drawing rolls.

When the clearer is swung downwardly into operative position as is shownin Figure 1, the apron will be brought into contact with all of thedrawing rolls. The clearer rollers are freely movable in a verticaldirection due to their free mounting in the grooves of the bearingblocks, and these rollers will keep the, apron in firm contact with thedrawing rolls. The heavy, weighted roll-er 32 will press the apronagainst the top back drawing roll with suflicient force to cause thedrawing roll to impart motion to the apron. The other clearer rollersbeing lighter will have no driving pressure upon the apron. As thedrawing rolls are rotated at progressively increasing speeds from therear rolls to the front and the apron k is moved at a speed comparableto that of the rear rolls, there will be a differential in surfacespeeds between the apron and the rest of the drawing rolls which willresult in a sliding or wiping motion of the drawing rolls against thebottom flight of the apron. Any lint or fiber picked up by the drawingrolls will be caught by the nappy surface of the apron and the slidingmotion between the apron and roll will cause it to befelted into thematerial. The surface 2:; of the pressure rolls, being made of syntheticrubber of the composition above noted, has just the right amount ofsurface frictional contact to carry the roving 5 through the drawingrolls without grabbing and pulling it apart and yet has just sufficientfrictional properties so as to pick up the loose and short fibers andpush this cotton waste against the clearer cloth to the extent that itforms a very firm felted condition. This same peculiar frictionalsurface of the pressure rolls makes it possible to utilize a mediumsized roll placed above the pressure rolls whereby to drive the clearercloth without any extra mechanical devices.

The apron is in continuous motion and carries away the picked up wastepresenting fresh portions of its surface of the rolls. Due to themovement of the apron and the fact that the waste is felted into thesurface of the apron material,

large quantities of waste can be picked up before the apron becomes sofilled with fibers that it will no longer function to clear the drawingrolls. This materially reduces the frequency with which the machine mustbe shut down in order to break the felt and strip the waste from theclearer cloth.

All of the clearer rollers float freely and may shift their angularpositions to agree with that of the particular drawing roll which theyoverlie and thus ensure contact between the drawing rolls and apronregardless of any misalignment of the drawing rolls. This also providesconstant pressure of the weighted roller 32 throughout its length uponthe apron to secure uniform frictional engagement between the apron andthe top rear driving roll and continuous movement 6f the apron while themachine is running.

Figures 5 and 6 illustrate a modified form of clearer employing aplurality of aprons instead of the single apron described above.

In this form of the invention the housing 34 is of substantially thesame shape as that of the first form, and is secured to end castings 35and 36 which take the place of the bearing blocks and stiffening orbracing frame members of the first form. The end castings are providedwith vertical slots 31, 38 and 39, 40 to receive the reduced ends ofrollers 4| and 42 formed of the same synthetic material as the toppressure rolls 2, and slots 43 and 44 to adjustably position alongitudinal brace 45 extending the length of the clearer housingbetween the end castings. Cover plates 46 and 41 of sufficient size toextend across the two front slots on each end casting preventaxialmovement of the rollers 4| and 42. Extensions 48 and 49 of the endcastings provide hinge arms for pivotal connection between the-clearerand the textile'machine.

Near therear edge of the clearer a strip 50 is fastened to the undersideof the housing. A plurality of U-shaped' stirrups 5| are fixed to thestrip 50 arranged in spaced groups of two intermediate the ends of thestrip, with a single stirrup near each end of the strip. Relativelyshort weighted rollers 52 are loosely mounted for rota tion in thestirrups and are free to move vertically within the stirrups. Aprons 53of substantially thesame width as the weighted rollers 52 are placedabout the clearer rollers. Therefore, the clearer contains a pluralityof aprons, with each apron having an independently mounted weightedroller to press its apron against the drawing roll. Both forms ofclearer disclosed herein are similar, as each ha all ofitsapron-supporting rollers free to move in vertical planes, and each has aweighted; roller to provide frictional driving contact between the apronand the top rear drawing roll, and lighter weight rollers at the frontof the clearer to keep the apron in contact with the other faster movingdrawing rolls to secure a sliding or wiping action of the rolls againstthe apron.

As a modification, the drawing frame assembly of Figure 1 may have asecondary clearer generally designated as at 60 in Figure 1, mountedbeneath the lower driving rolls 2. In such a modification a secondclearer belt 33a would be used for contacting the lower set of rollers 2the same way that the clearer belt contacts the upper set of rollers 2.In case such a bottom clearer member would be used the surfaces of thelower set of rolls 2 would be formed of the same synthetic material asthe surfaces 2a of the upper set of rolls 2. Such bottom clearer wouldnot need to be covered as the top clearer 6 but need only be lowered outof position to remove the felted waste.

It will thus be seen that I have provided a drafting frame assemblywhich brings together a new combination of elements which in actualcommercial use has resulted in the production of a much better cottonyarn with far less supervision and less maintenance cost than has beenpossible with standard devices used in the past.

Cork and rubber pressure rollers have, in combination with stationaryclearers, worked with a fair degree of success, but these same rollershave not been satisfactory with revolving clearers while, on the otherhand, synthetic rollers such as shown in Rockoff when attempted to beused as replacement for cork and rubber rollers with stationary clearercombinations have not proven satisfactory. However, by combiningsynthetic surface pressure rolls with a particular type of revolvingclearer I have produced a new combination in which the peculiarcoefficient of friction of the pressure rolls cooperates with theclearer cloth so that rolls have just sufficient frictional propertiesto pick up the loose and short fibers and carry them on the roving andpush or attach this cotton waste against the clearer cloth, at the sametime this frictional surface is such it will not grab the short fibersand pull them around the pressure rolls as has been the case with rubberand cork pressure rolls when used with revolving clearers, nor does itpile up the short fibers in front of the pressure rolls as is the casewhen synthetic surfaced rolls are used with a stationary clearer.

What I claim is:

1. In a drawing frame assembly of the type having a revolving clearercloth, and a pressure roll for driving said cloth by friction, said r011having a driving surface formed of clear synthetic rubber like compoundwith a coefiicient of friction with respect'to the clearer clothsubstantially equivalent to that of a vulcanized composition comprisingby weight 100 parts perbunan, 5 parts zinc oxide, 2 parts sulfur, 1 partbenzothiazl disulfide, 30 parts whiting, 10 parts mineral oil and 30parts cotton fiber, such that all short fibers picked up by the rollwill be felted onto the cloth and the pressure rolls kept clean. 2. In adrawing frame assembly of the type having a revolving clearer cloth, anda pressure roll for driving said cloth by friction, said roll having adriving surface comprising butadieneacrylic nitrile co-polymer with acoeflicient of friction such that all short fibers picked up by 8 theroll willbe. felted'onto the cloth and the pressure rolls kept'clean.

- 7 RUSSELL B. NEWTON.

REFERENCES CITED The following references are of record in the file ofthis patent? UNITED STATES PATENTS Number Name Date 2,111,966 Davis Mar.22, 1938 2,258,033 Presley Oct. '7, 1941 2,304,656 Rockoff Dec. 8, 19422,341,656 Rockoff Feb. 15, 1944 FOREIGN PATENTS Number Country Date .153Y Great Britain 7 of 1858 3,386 Great Britain of 1873 4,491 GreatBritain of 1876 Austria Jan. 10, 1931

